Liquid fuels having the tektdeitcy to bubet with a



. E.STRAUB. FURNACE FOR BURNING LIQUID FUELS HAVING T-HE TENDENCY T0 BURN WITH A STRONGLY SOOTING FLAME.

- APPLICATION FILED NOV. 5. WW.

1 ,313, 1 36. Patented Aug.12,1919.

fl j I Z 2 'ing flame. In the furnaces holes.

EDUARD S'IBAUB, OF SULGEN, SWITZERLAND.

FURNACE FOR BURNING LIQUID FUELS HAVING THE TENDENCY I v STRONGLY-SOOTING FLAME.

TO BURN WITH A Patented Aug. 12 1919.

Application filed November 5, 1918. Serial No. 261,244.

To all whom it may concern:

Be it known that I, EDUARD STRAUB, a citizen of the Republic of Switzerland, residing at Sulgen, SwitZerlancL'have invented certain new and useful Improvements in Furnaces for Burning Liquid Fuels Having the Tendency to Burn with a Strongly-Sooting Flame; and I do hereby declare the following to be a clear, full, and exact description of the invention, such as will enable'others skilled in the art'to which it appertains to make and use the same, -reference being had to the accompanying drawing, and to figures of reference marked thereon, which form a part of this specification. r This invention relates to improvements in furnaces for burning liquid fuels having the tendency to burn with a strongly soothitherto proposed it is only possible to'burn liquid fuels so as to prevent a clogging of the air passages when provision for a supply ofcompressed air is made.

For this reason it was not possible to use till now liquid fuels in' furnaces workingonlywith a natural'a'ir draft.

V The object of the present invention is to pr ovidea furnace for burning liquid fuels working with a natural air draft in which no sootis produced. I I

The furnace according to the present invention comprises a flat cup resting on legs and arranged at the beginning of a channel in which a natural air draft is produced.

This cup has a front wall causing the air drawn through said channel to stream at a certain distance above the flat cup past the latter. The furnace according to this invention comprises also means for supplying liquid fuel to the'front wall of the cup, which fuel vaporizes as soon as it comes in contact with the Hat bottomed portion of the cup, the current-of air present above this cup portion" flowing in a direction forming a right angle with the vertically rising vapors of'fuel. Preferably the bottom of the cup is provided with a plurality of The invention consists also in the part cular construction, arrangements and c'om b1nat1on, of parts of the furnace, as will "hereinafter be fully set forth and pointed out in the'claima referenc'e being had to the e c mpenyme" rewmes lns by y is pre-heated.

Fig. 4 isa section on the line IV IV of Fig. 3, and

F 5"is a view corresponding to Fig. 3

showing a modification of-a detail:

Figs. 6 and 7' show another form of the example several embodiments of the invenfront wall of the furnace,"';Fig;"7 being-*3.

section on the line VII VII of Fig. 6.

Referring to the drawing, 1 denotes a mufiie arranged within the'heating chamber of the furnace and exposed on all sides to the heating action of the combustion gases. The flues of the furnacecomprise a channel 2 guiding the 'combustion gases from the combustion chamber or space 3*intothe heating chamber "7; The latter communicate's by means of passages 8 8" with horizontalchannels or flue's 9," 9 connected at their turn with vertical channels '10, 10 communicating with horizontal channels 11, 11-. The latter are connected by means of passages 12, 12 with acommon'flue 13 communicating with the.chimney of the furnace, which chimney is not shown on the drawing.

4 denotes a' pivotally mounted hood provided near the outer end ofthe combustion space 3 and causing the air for-combustion streaming through a vertical channel '6 and a horizontal channel 5 arranged below the combustion sp'ace 3 and the horizontal channel 2 to pass into the space [3; The channel 6 communicates at its upper end with the atmosphere. As shown in Fig. 1, the channel 5 provided for the supply of fresh air is arranged near the combustion space?) and the flue 2, so that the air passing through it Theifurnace proper is arranged at the beginning of the flue wit-hinthecombustiqn chamberB. It comprises a cup 17 '(Fig. 3) resting on four legs--19 'formed' integral therewith; the air for combustion is adapted to come, on all sidesin "contact with said cup. The cup is very' flat and it is pro- Vi ded in its bottom port-ionfwith plurality of tube-l'ike'holes 20. The cup comprises further a front wall 16 projecting beyond the bottom portion of the cup. 23 denotes a supply pipe for the liquid fuel.

18 denotes an adjustable covering plate having the shape of an angle iron and adapted to be placed in front of the cup when it is desired to prevent the air for combustion from coming in contact with the bottom of the cup 17.

14 is a plate arranged above the combustion space 3, a narrow passage 15 for the air for combustion being provided between the plate 1% and the upper end of the front wall 16 of the cup.

In the furnace shown in Fig. 5, the rear end of the cup 17 touches the bridge 3 of the flue, while in the furnace shown in Figs. 1- l a certain space is provided between cup 17 and bridge 3 In the second embodiment no covering plate 18 is required.

The furnace shown in Figs. 6 and 7 com prises a cup 17 having a front wall 16 extending up to the plate l-Il; and provided with an opening 22.

The working of the improved furnace is as follows lVhen the cup 17 has been filled with a small quantity of liquid fuel, the latter is ignited and the hood 4: is then closed. The air for combustion flows now in consequence of the natural air draft present within the channels 6 and 5 through the latter and passes then into the hood 4 and from the latter, at a certain distance above the flat portion of the cup 17, into the combustion space 3 where it comes in contact with the vertically rising and at first strongly sooting flame of the burning fuel carrying thereby with it the gases, which contain for the present still much carbon. Owing to this, a further layer of the burning fuel is caused to come in contact with the highly pro-heated air for combustion, a perfect combustion of the fuel being thus attained and a very high temperature being produced beneath the muffle 1. In consequence of the fact that the air for combustion enters near the top of the chamber 3 into the latter, the flame is not deflected downward bv said current of air, so that a very intimate contact between the hot combustion gases and the muffle 1 is obtained. The temperature produced within the combustion space 3 has the effect to heat the cup 17 gradually to such a temperature that the fuel still contained in the cup is vaporized and caused to burn. When this is the case, liquid fuel is supplied to the cup 17 through pipe 23, a member controlling this supply being adjusted in such a manner, that the liquid fuel dripping on the cup 17 is immediately vaporized owing to the high temperature of the cup. The current of air caused to stream in consequence of the natural air draft present in the furnace from the hood 4: into the combustion chamber 3, crosses at right angles the fuel vapors rising from the cup 17, so that the air for combustion and said vapors are caused to mix in a very intimate manner producing thereby a mixture which burns without producing any soot.

It will be seen, that in the furnaces according to the present invention the air for combustion is only able to mix with Vapors of the liquid fuel and not with the liquid fuel itself, and that oxygen is supplied in such a quantity to provide for a complete combustion of said vapors, thus avoiding any production of soot which is always produced only in consequence of an imperfect combustion and a too low temperature of combustion.

I claim:

1. A furnace for burning liquid fuels having the tendency to burn with a strongly sooting flame, comprising a flue with a natural air draft, a vaporizer plate arranged within said flue adapted to be heated by the combustion taking place in said flue above the evaporating temperature of the liquid to be burned, the longitudinal axis of the plate extending in the direction in which the air of combustion admitted before said plate into the flue has the tendency to stream through the latter, and means to sprinkle from above and at right angles to the current of the air of combustion streaming through the flue, liquid fuel in such a quan-- tity to said vaporizer plate during normal working of the furnace that all the supplied liquid coming in contact with the heated vaporizer is vaporized at once.

2. A furnace for burning liquid fuels having the tendency to burn with a strongly sooting flame, comprising a flue with a natural air draft, a heating chamber communicating with the flue, a muflie arranged within the heating chamber, a very flat cup arranged within said flue before the heating chamber, the cup supported above the bottom of the flue being so arranged as to extend with its longitudinal axis in the direction in which the combustion air admitted before the cup into the flue tends to flow through the latter, and said cup having perforations through its bottom, and a baflie wall extending transversely across the whole flue in order to direct a portion of the combustion air over the cup, means for regulating the passage of air through said perforations, and means adapted to sprinkle from above and at right angles to the current of air directed over the cup liquid fuel in such a quantity to said bafile wall during normal working of the furnace, that all the supplied liquid coming in contact with the heated cup is vaporized at once. 7

3. furnace forburning liquid fuels having the tendency to burn with a strongly sooting flame, comprising a flue provided with a bridge near its begmning and having a natural air draft, a flat cup arranged within said flue at its beginning, legs for supporting the cup, the latter touching on one side the bridge of the flue the upper edge of which lies on the same level as the upper surface of the flat bottom of the cup provided with holes, said cup having also a front wall extending vertlcally beyond its bottom, thereby causing the air for combustion to flow at a distance above said bottom past the cup, and means for supplying a liquid fuel to said cup, the vapors of fuel rising vertically from the cup being crossed at right angles by the air for combustion.

A furnace for burning liquid fuels having the tendency to burn with a strongly sooting flame, comprising a flue provided with a bridge near its beginning and having a natural air draft, a fiat cup arranged Within said flue at its beginning, legs for supporting the cup, the latter touching on one side the bridge of the flue the upper edge of which lies on the same level as the upper surface of the flat bottom of the cup provided with holes, said cup having also a front Wall extending vertically beyond its bottom, thereby causing the air for combustion to flow at a distance above said bottom past the cup, means for supplying from above a liquid fuel to said cup,- the vapors of fuel rising vertically from the cup being crossed at right angles by the air for combustion, channels for supplying preheated fresh air to the flue, and a pivotally mounted hood arranged in front of said flue and directing the pre-heated fresh air from said channels into the flue.

In testimony that I claim the foregoing as my invention, I have signed my name.

EDUARD 'STRAUB.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents,

Washington, D. G." r 

